The embodiments described herein relate generally to motors, and more particularly, to methods and systems for controlling power delivered to an electric motor.
Electric motors are used in a variety of systems operating in a variety of industries. Electric motors are used to power products such as fans used in heating, ventilation and air conditioning systems (HVAC). Energy losses occur during a thermodynamic cycle of refrigerant in a heating, ventilation, and air conditioning (HVAC) system. Some of the dissipated energy may be recovered or regenerated using a low power turbine-generator assembly. Typically, energy is regenerated back to an electrical grid. Regeneration to the grid requires extra components, which can make it impractical and inefficient to regenerate energy to the grid. Moreover, known systems that regenerate energy rely on the regeneration source to “compete” with a conventional power supply to provide energy to the electric motor. That is, the regeneration source can only provide power to the electric motor when its terminal voltage is greater than the terminal voltage of the conventional power supply. Accordingly, until the amount of generated voltage reaches and exceeds the amount of power being supplied by the power supply, the regenerated energy is not used. Such known systems result in wasted energy and lack of control of supplying power to the electric motor.